The field of the present disclosure relates to vibratory screening machines and conveyors using flexible mats.
Various designs have been proposed for sieve mat screening machines. One prior screening machine has an elongated support frame with a mobile, deformable sieve mat, typically comprised of a plurality of sieve mat sections and a series of alternating first and second sieve mat supports mounted on the support frame and extending transversely along the length thereof, the sieve mat sections being affixed to a pair of the first and second mat supports with the mat supports being movable with respect to each other in the direction of the length of the support frame. During cycling of the screening machine, the individual screen mat sections are alternately tensioned and relaxed creating a high-acceleration trampoline effect. For the purposes of this description, this machine is referred to as a flip-flow type screening machine. Certain flip-flow machines are described in LaVeine et al U.S. Pat. Nos. 7,654,394 and 7,344,032.
The present inventor has recognized potential for improvements to the prior sieve mat screening machines.